Swapping D16Z6 (93 ex) into 91 hatch std.

91 hatch undergoing a swap from a 93 ex. I have the entire car so I will be swapping as many components as possible with the assistance from fellow honda swap members. I will post progress photos to keep this thread interesting and you guessed it "educational." From what I have heard this swap is fairly simple especially since I have the entire car I am pulling the donor drive train from. This will be my first swap so I have many questions. I plan on swapping over the entire 93 ex wire harness and ECM.

For starters after briefly looking over both engines, I noticed the 91 does not have the lower engine/tranny mounts found on the 93 It does however have a tranny mount that braces to the front cross member. I also noticed the difference in clutch engaging. The 93 uses a hydraulic clutch and the 91 uses a cable. I will start this thread with that and wait for experienced answers from "been there done that" members.

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ok first off you can use the tranny from the 91 and bolt it up to the d16z6
the mounts,linkage,axles,and everything are the same..
if your car is dpfi you will need to change it to mpfi(look in the tech section and there is a writeup on how to do it...
you will need an obd0-obd1 conversion harness(www.rywire.com) and the ecu out of the 93

Thanks for the post. I would rather use the 93 tranny for the 5 speed vs 4speed. I checked out hasport.com and it appears they sell conversion kits for cable to hydro. Or maybe get me some opinions on which tranny to go with. Ive read few pros on cons from other threads. It seems an updated 5 speed is the better way to go providing linkage will still function correctly.
Also, if I swap the entire harness from the 93 will I still need a conversion harness. Yes the 91 is dpfi(dual point fuel injection)

Again thanks for the posts. Its proven that in order to swap from cable to hydro or hydro to cable pre fabbed mounting brackets will be required and can be purchased from a few different companies. Depending on how far somebody wants to go with a swap, will vary if it is worth it.

I think for me, I will settle for a motor only swap, thus keeping the cable operated tranny. If I were to go with say a B18 or better I would proceed with a hydro clutch for obvious reasons. (some may disagree)
Following "injens" advice Im going to purchase a harness adapter for ease of installation.

After reading several different threads, it appears the swap I will be performing will be direct bolt in with very minimal mods. The D16 will not use the lower mounting bracket on the alternator side. It seems the transmission mount (mounts to front cross member) on the ef (91) should be sufficient.

Further posts are welcomed and appreciated. I will post progress work.

If you have the4 speed tranny then if you want to upgrade to the 5 speed you will have to upgrade the hubs out of a si or hx civic or crx. If you keep the 4 speed however you will not have to worry about anything like that.

Justin..So what your saying is if I did decide to go with the ex 5 speed hydro tranny I would need to use the axles you specified. I made the decision to stick with the 4 speed cable actuated tranny, mainly because Im not going huge on the swap. So if anyone is interested in buying this 5 speed tranny let me know.

I have been contemplating on this subharness that sells in the neighborhood of $300 which is about what I paid for the whole car. I have both harnesses and both cars. It seems its just a matter of exchanging/deleting and swapping wire pins and plugs. There are some very experienced peeps on this site alone that can explain what needs to be done. Am I right?

I've never attempted or actually done a swap of a vtec engine into a EF and made it run how its suppose to from factory. but as long as your little EF is a Si or you happen to have the harness to make it Si. then you can just bolt the engine right on in, switch injectors, dizzy, o2 sensor, and some other nic naks to obd-o. But here is another way of running your vtec better. Ive been told by just adding power to the solenoid doesnt really let vtec hit hard at all. what i was told is you can run a steal braided line, from where your "orginal" oil pressure sensor on the back of your engine right above the oil filter, and run it to a little block off cap between your dizzy and solenoid and that gives you the oil pressure you need. but thats if you really want to rig something. im NOT suggesting you go out and do this. im only give you an option. Ive never tried this either.

i really wouldnt suggest putting the obd-1 harness in place of the obd-0. especially since this is your first swap.

In response to 94H_ex, I appreciate your post, but you completely lost me. From what you mentioned it being a "rig" defines it precisely. I couldnt imagine installing obdo components on this motor designed to perform with obd1. Again, I am no expert but just the fact of having to run the "oil pressure line to a little block off cap" does not seem promising or reliable to me. Also, after doing a little research both obd0 and obd1 harnesses will have to be combined and interchanged to make this happen. So it would not be installing the obd1 harness "in place of" the obdo0.

Blanco..rywire is the company that charges $300 plus shipping for the harness I will need. I searched the forum you mentioned, and found most advertising the hell out of rywire for their product, and they are shuttin down shop and vacating for a month on the 8th of AUG(must be nice). I will search it more and see what I else I can come up with, or paypal you the 20 for the search leg work. Injen gave it a +1 does that mean he gets a cut? hahaha

There's some misinformation on this thread; but I haven't gone through much of it.

Keep your stock axles. The only thing different than the 5-speed axles is the spline count/size at the wheel hub. This means that you can run any 88-00 D-series transmission so long as you keep your stock axles. You can always swap hubs though and run 88-91 5-speed axles; but you'll just be spending more money. For the transmission, if you're looking for performance just get a 88-91 Si transmission(89-91 recommended due to clutch difference with the 88s).

The mounts between them are also different. Swap over your stock 91 mounts onto the engine and transmission. I'm assuming you have a Std, which is what I have; the transmission mount on there is even different from the DX/Si; it's narrower.

Since you have a donor car, you could do what I did(which I must say, is VERY timing consuming), is retrofit the OBD1 harness into the OBD0 car. It's about 20 wires IIRC that would need to be soldered in or spliced in. A cleaner route is MPFI conversion then OBD0->OBD1 conversion.

K2e2vin..good info on the axel situation..would you happen to have any type of diagram showing which 20 wires you mentioned need to be "retrofitted"? I am good with wiring and can keep it clean providing I have a diagram to follow. The cleaner route you mentioned(mpfi conversion) must be the harness blanco mentioned rywire sells for the $104.

Blanco..would you also happen to have a diagram or any type of instruction to perform what you mentioned. I am about to be here do this, it sounds like you been there done that. I feel like I may be trying to perform this like a blind sighted rookie otherwise My offer is still valid for leg(finger) work copy/paste.

Sorry I don't have a diagram. Not many people go this route so I pretty much had to go through a Civic/CRX wiring diagram and 92-95 EX/Si wiring diagram. It's like 7 wires on the driver's side harness, maybe 10 on the engine/passenger harness side that needs to be wired in and the rest goes through to the "main" section. This is a good route if you plan on tucking the wires anyways.

What I did was pretty much cut out the harness from the ECU to the engine(so OBD0 harness was removed, and OBD1 one fitted in); and was left with a couple of wires. Just find out where the wires go and splice it into the vehicle main harness. There's some wires on the driver side that needs to be reverted back to the passenger side also(like starter signal, etc.), and a couple of wires(like maybe 4 or 5) that goes into the OBD0 driver's side connector. I don't remember everything in exact detail but that's pretty much it in general. I still need to clean up my wiring though(excess wire everywhere, although wrapped up and tucked away) because when I did it, I was in a rush just to get the car started.

awptickes..My thoughts exactly when I brought home the 93 eg. I figured it would be exactly that simple from the get go. Like I mentioned at the start of the thread I do have both cars both complete and this is my first swap. "Injen" was first to post and immediately stated I will need a conversion harness.
With his rep power and over 3000 posts I hold faith what he stated is indeed a fact. Along with "blanco" who has a reputation beyond repute states a conversion harness is a must. Im sure if it were possible to do as you stated, these 2 members would have stated it from the get go. I am still all ears or eyes in this case if anybody objects. I should have the motor pulled by tonight.

You can do the entire harness swap. It'll require taking the dash out and rewiring everything behind it, as well. You'll either have to cut the cannon plugs off of the cabin harness and solder them back on, or map and depin them all. Either way, it's going to take considerably longer to do it that way.

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That's what I was thinking. Hrm. Depends of how much the OP likes working in cramped spaces under the dash.

After taking a look at the wire harness that runs along the firewall out of the ECU on the 93 eg, I decided to definitely go with a conversion harness. This particular ex is a japan made which ( I think) means it has every option honda ever offered in a civic. ( 2 inch+ thick wire loom) most of which I would not use. By the way, if anyone is looking for parts from a 93 ex, let me know. (minus the engine obviously)
Anyway, pulled the engine from the ef tonight. In all reality it was fairly easy. (I apologize for some of the blurred shots.) Be sure to remove the alternator first unless your car does not have an A/C compressor. Time to clean up the engine compartment on the EF and get ready to pull the Z6 (mini me)

Justin..what dash/console is that in your ef? looks sweet. Do you know of anyone that would swap my hydro 5 speed for a cable 5 speed? I have heard a few members mention that the 4 speed is an agressive tranny and has taller gears which is beneficial for VTEC. What is your 2 cents on that? Anyway, pulled the Z6 tonight from the eg. It was a little more challenging than the ef. I had to tilt it quite a bit to detach the rear mount. I guess I have some tranny swappin to do.